1. Field of the Invention
The present invention relates to vented container covers and, more particularly, to a cover assembly designed for the filtered venting of a container, such as, for example, the reservoir holding the drive fluid of a hydraulically operated production machine.
2. Description of the Prior Art
In order to protect the hydraulic drive fluid of a production machine from contamination by ambient particulate matter, it may be desirable to contain the hydraulic fluid in a closed, vented reservoir. An optimal degree of protection is obtained with a fluid reservoir which includes, in its vent passage, an air strainer in the form of an interchangeable filter cartridge.
The use of an air filter in conjunction with a vent opening on a hydraulic fluid container is known from the prior art. A known device of this type features a vent opening in the reservoir wall, a flanged filter casing screwed to the outer side of the wall, and a removable threaded cover on the distal end of the filter casing.